Hi, my wife's 2000 520i runs silky smooth and idles fine, but has recently picked up the habit of stalling. It is automatic and sometimes stalls when pulling out of junctions- very embarrassing and rather dangerous ! It does this probably two or three times a week, the engine warning light is not on and I have replaced the fuel and air filters and the air flow meter.

It is always when you have slowed down for a junction then try to accelerate away,but sometimes it won't do it for days. It has recently had a MAF and fuel filter. I was wondering about changing the O2 sensor, but thought this would cause the problem to be constant not just now and then.
Many Thanks, Nigel

o2 sensors ,would not cause that if any thing maybe some rough running,does it feel as you let go of the clutch pedal and stall or is just engine the dies and when it dies is it just sudden or does it start idling bad then dies.

Thanks I'll give it a go. I found a split in a vacuum pipe on my 330d at the weekend, and Wow what a difference it makes when the turbo is spinning properly! I would never have thought an innocent unimportant looking pipe could make so much difference!